Abstract:
Chemists in South Korea have created hollow molecular spheres by polymerising a simple, flat building block without the help of any scaffolding or template to create the three-dimensional shape.

Kimoon Kim and colleagues at Pohang University used a hollow building block called a cucurbituril. These take the form of molecular ribbons rolled up into cylinders. Cucurbitils were named after the plant family to which pumpkins belong, because of their hollow shape. They have served as hosts in supramolecular chemistry, accommodating guest molecules such as spermine.